linux-ext4 - Re: [PATCH -v2] ext4: Use inode preallocation with -o noextents

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080605191251.GC4723@skywalker>
Date:	Fri, 6 Jun 2008 00:42:51 +0530
From:	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>
To:	Andreas Dilger <adilger@....com>
Cc:	Theodore Tso <tytso@....edu>, cmm@...ibm.com, sandeen@...hat.com,
	linux-ext4@...r.kernel.org
Subject: Re: [PATCH -v2] ext4: Use inode preallocation with -o noextents

On Thu, Jun 05, 2008 at 12:28:30PM -0600, Andreas Dilger wrote:
> On Jun 05, 2008  11:37 -0400, Theodore Ts'o wrote:
> > This is better, but it still means that we are exporting a large
> > number of functions to the callers.  It's not clear to me we need so
> > many different variants of ext4_new_blocks_* --- what is their
> > justification to exist?
> > 
> > For example, why not just have:
> > 
> > static ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
> >        				ext4_lblk_t iblock, ext4_fsblk_t goal,
> > 				unsigned long *count, int *errp, int meta)
> > 
> > where if inode is NULL, then you're allocating a metadata block, and
> > if count is NULL, then you only want one block.  Of course, this needs
> > to be carefully documented at the function.
> 
> I don't necessarily agree that meta should be implied by inode != NULL.
> We do want to cluster metadata allocations for a single inode if possible,
> so keeping the inode information is useful.  We may want to keep a separate
> "metadata goal block" from the "data goal block" in the inode...
> 
> That said, it seems you still have a "meta" parameter here?  I always hate
> having an int for a boolean, and we may as well make this a "flags" so
> that when we want to improve it later we don't need to rename it and change
> all of the "1" parameters to "EXT4_META_BLOCK".  Do it right the first time.
> 

how about ?

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index c6e6a6f..014e5b5 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -1928,9 +1928,11 @@ ext4_fsblk_t ext4_orlov_new_blocks(handle_t *handle, struct inode *inode,
        return 0;
 }

+#defin EXT4_META_BLOCK 0x1
+
 static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
                                ext4_lblk_t iblock, ext4_fsblk_t goal,
-                               unsigned long *count, int *errp, int meta)
+                               unsigned long *count, int *errp, int flags)
 {
        struct ext4_allocation_request ar;
        ext4_fsblk_t ret;
@@ -1950,7 +1952,7 @@ static ext4_fsblk_t do_blk_alloc(handle_t *handle, struct inode *inode,
        ar.goal = goal;
        ar.len = *count;
        ar.logical = iblock;
-       if (S_ISREG(inode->i_mode) && !meta)
+       if (S_ISREG(inode->i_mode) && !(flags & EXT4_META_BLOCK))
                ar.flags = EXT4_MB_HINT_DATA;
        else
                /* disable in-core preallocation for non-regular files */
@@ -1965,13 +1967,15 @@ ext4_fsblk_t ext4_new_meta_block(handle_t *handle, struct inode *inode,
                ext4_fsblk_t goal, int *errp)
 {
        unsigned long count = 1;
-       return do_blk_alloc(handle, inode, 0, goal, &count, errp, 1);
+       return do_blk_alloc(handle, inode, 0, goal, &count,
+                                               errp, EXT4_META_BLOCK);
 }

 ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode,
                ext4_fsblk_t goal, unsigned long *count, int *errp)
 {
-       return do_blk_alloc(handle, inode, 0, goal, count, errp, 1);
+       return do_blk_alloc(handle, inode, 0, goal, count,
+                                       errp, EXT4_META_BLOCK);
 }

 ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html